Feasibility and utility of Venous Excess Ultrasound Score to assess fluid status postoperatively in patients with severe pre eclampsia and eclampsia following lower segment caesarean section - a prospective observational study

Thorough preoperative evaluation and necessary investigations are carried out and written and informed consents of patients/ patient attenders of age 18 to 40 years females with severe Pre eclampsia and eclampsia scheduled for emergency lower segment cesarean section are taken

VExUS protocol-guided ultrasound scanning shall be performed, postoperatively at 0 hour, 6 hours and approximately 24 hours postoperatively (in High Dependency Unit /Post surgical intensive care unit). Scans will be completed using the curvilinear probe(2-5MHz) Sonosite S2 US machine.

Initially Transthoracic echo will be performed in supine position to rule out right heart dysfunction and other cardiac pathologies. Then IVC will be visualised in the subxiphoid window, but  would elect for midaxillary window if necessary. The IVC diameter will be measured in long axis with special attention taken to observe widest perpendicular diameter. The hepatic, portal, and intrarenal veins will be visualized in the midaxillary window and the posterior axillary window with patient in supine position.  Focused effort would be made to scan the main hepatic, main portal, and interlobar renal veins and not the possible other branches of each respective vessel. To obtain sufficient doppler signals, breath holding would be conducted to stabilize the diaphragm and secure adequate windows. This brief breath holding would be done at various points throughout the respiratory cycle depending on what would elicit the best anatomical views for using doppler. Then pulsatility index of these veins will be calculated. The ultrasonographic examination will be done by the Post graduate under the supervision of the guide. The Post graduate would have performed at least 50 examinations (50 patients) under the guidance of the experienced guide in the pilot testing before actual recruitment of patients.

Based on the findings of the above mentioned veins VExUS grading will be carried out as follows:

Grade 0 : No Venous congestion, IVC < 2cm

Grade 1 : mild Venous congestion, IVC > or = to 2cms + any combination of normal or mildly abnormal waveforms

Grade 2 : moderate Venous congestion, IVC > or = 2cms + at least one severely abnormal waveform

Grade 3 : severe Venous congestion, IVC > or = to 2 cms + 2 or more severely abnormal waveforms

Data management and statistics:

The data will be entered in MS Excel sheet cleaned and the averages/ means proportions /diameters/ pulsetility index percentages/ gradings are noted. The continuous variables related to the IVC diameters, waveforms and pulsatility index of the hepatic vein, portal vein and intrarenal veins at different intervals of 0 hour, 6 hours and 24 hours post operatively are expressed in centimetres and percentages. Grading according to the VExUS grading protocol will be expressed. And the other data related to the patients characteristics such as age, address ,diagnosis ,basal vitals and the vitals trends intraoperatively and the other data related to the patient will be entered as necessary. The data will be checked for uniformity of distribution